Development east of the Anacostia River got a shove yesterday from Mayor Anthony A. Williams when he proposed that the Metro system sell its valuable downtown headquarters and build an office complex on empty land at a rail station in Southeast Washington.

Williams (D) said he also wants the city to build a mid-size municipal building at the Anacostia Metro station. Together, the projects would bring more than 1,300 daily workers to an area that is a 10-minute drive or train ride from downtown but is desolate, save for the morning and evening rush of commuters through the station.

The proposal comes at a time of unprecedented focus on the economic development potential of the Anacostia River, the waterway that has served as a painful socioeconomic dividing line.

A stadium for the Washington Nationals is the best-known project planned for the river's western side, near the booming Navy Yard area. A headquarters for the U.S. Department of Transportation is under construction there, and thousands of residences are planned.

Last month, President Bush asked Congress to give the city control of 110 acres of parkland on the eastern side of the river, opening the door for housing, a major museum or memorial and a waterfront park. The D.C. United soccer team has expressed interest in building a stadium in the area.

Williams's Anacostia Waterfront Initiative includes a host of other amenities along both sides of the eight-mile waterfront: neighborhoods, shops and cultural attractions; redesigned roads and bridges; and a river-walk trail.

"The momentum is there," Williams said. "WMATA would be adding greatly to it."

Several Metro board members said they were interested in selling their eight-story headquarters, east of MCI Center at Fifth and F streets NW. Real estate analysts said the building, which covers a city block, could sell for upward of $75 million. It was completed in 1974, when the East End itself was a neighborhood in need of renewal.

But Metro board Chairman T. Dana Kauffman questioned whether moving Metro's main operations control center, along with about 1,100 managers and employees, would be cost effective.

"It's not just a question of unplugging the PC and rolling it out. We'd have to relocate the brains of the operations control center," he said. "If it has a significant upside that we can turn into a real benefit for customers -- that's one thing. But if it's just a development opportunity for a jurisdiction, that's another."

Dan Tangherlini, D.C. transportation director and Metro board alternate, said it would be a boon to move the operations center, which, like the building, is outdated.

The center, he said, "is high-tech circa 1985. Why not sell the stuff that's worth a lot, in an old building in need of updating, and use the opportunity to get a new one?"

Metro board member Charles Deegan, who represents Prince George's County, said the cash-strapped agency should leverage its downtown asset: "The bus company doesn't have to be in the high-dollar neck of the woods."

The Anacostia Metro site, which the transit agency unsuccessfully tried to sell last year, spreads over 5.25 acres, officials said. About 3.5 acres are available for development. Williams said the site could support housing and retail, as well as offices for city agencies now renting elsewhere. The complex also would include headquarters for the Anacostia Waterfront Corp., a publicly chartered company created to steer redevelopment along the river.

The D.C. Council passed legislation requiring the corporation to locate east of the river rather than on the more-developed western side. Council member Marion Barry (D-Ward 8), a vocal proponent of that legislation, issued a statement yesterday saying he strongly supported Williams's proposal.

"We welcome the growth because of the potential for bringing more positive activity and jobs to our area. . . ," Barry's statement said. "We're just glad our time has come."

Williams called Barry the inspiration for the proposal, which he said was modeled after Barry's effort as mayor to trigger revitalization of the 14th and U Street corridors by locating the Reeves Municipal Center there.

Building at the Metro station would add a hub to the Anacostia neighborhood, which is showing signs of recovery after decades of decline.

Eight blocks north along Martin Luther King Jr. Avenue, at the foot of the 11th Street bridges, an office and retail complex called the Anacostia Gateway broke ground last month.

King Avenue, which winds through the Anacostia business district, is starting its third year in the Main Streets revitalization program, which uses marketing and strategic planning to enhance existing businesses and attract new ones. The city's first light-rail project is also planned for the neighborhood.

An office complex would mean "more workers and increased customer base" for businesses and storefronts along the blighted street, said Yavocka Young, executive director of the Main Streets project. "I think it would be a great opportunity."

Staff writers Steven Ginsberg, Lindsey Layton and Lori A. Montgomery contributed to this report.